Created Matrix2x2-class.

src/main/java/edu/ntnu/stud/model/Matrix2x2.java

+package edu.ntnu.stud.model;
+
+/**
+ * Class representing a 2x2 matrix.
+ */
+public class Matrix2x2 {
+
+  /**
+   * The a00 component of the matrix.
+   */
+  private double a00;
+
+  /**
+   * The a01 component of the matrix.
+   */
+  private double a01;
+
+  /**
+   * The a10 component of the matrix.
+   */
+  private double a10;
+
+  /**
+   * The a11 component of the matrix.
+   */
+  private double a11;
+
+  /**
+   * Create a new 2x2 matrix.
+   *
+   * @param a00 The a00 component of the matrix.
+   * @param a01 The a01 component of the matrix.
+   * @param a10 The a10 component of the matrix.
+   * @param a11 The a11 component of the matrix.
+   */
+  public Matrix2x2(double a00, double a01, double a10, double a11) {
+    this.a00 = a00;
+    this.a01 = a01;
+    this.a10 = a10;
+    this.a11 = a11;
+  }
+
+  /**
+   * Multiply the matrix by a vector., i.e. compute the product of the matrix and the vector.
+   *
+   * @return The a00 component of the matrix.
+   */
+  public Vector2D multiply(Vector2D v) {
+    return new Vector2D(a00 * v.getX0() + a01 * v.getX1(), a10 * v.getX0() + a11 * v.getX1());
+  }
+
+}